Packaging Ruby Libraries with RubyGems Dr Nic Williams - PowerPoint PPT Presentation

Packaging Ruby Libraries with RubyGems Dr Nic Williams drnicwilliams.com

Easier to write RubyGems than not to

Demo • create class and use it • save + run from cmd line • extract classes to file + require • show load path

$LOAD_PATH == $: ["/opt/local/lib/ruby/site_ruby/1.8", "/opt/local/lib/ruby/site_ruby/1.8/i686-darwin9.1.0", "/opt/local/lib/ruby/site_ruby", "/opt/local/lib/ruby/vendor_ruby/1.8", "/opt/local/lib/ruby/vendor_ruby/1.8/i686-darwin9.1.0", "/opt/local/lib/ruby/vendor_ruby", "/opt/local/lib/ruby/1.8", "/opt/local/lib/ruby/1.8/i686-darwin9.1.0", "."]

Relative require require File.dirname(__FILE__) + "/person"

Update $LOAD_PATH $:.unshift File.dirname(__FILE__) require "person"

Demo • break person.rb into person/*.rb files • use relative requirements within person.rb • add path to $LOAD_PATH and refactor requires

Where do tests go? • /test or /spec folder • then code needs own folder /lib • executable code in own folder /bin • #!/usr/bin/env ruby • add /bin to env path • chmod +x each file

Good project structure

Questions to ask • How do I share my project? • Where/how should other people install project? • Inter-project dependencies? • New project versions?

RubyGems • Packaged in .gem file • Installed into shared/central cache • Version numbers • Dependencies to other gems/versions • Community download site - rubyforge.org

NewGem - scaffolding • gem install newgem • newgem gem_name • creates scaffolding to new RubyGem project • rake -T -- lots of helpers to build + deploy

Demo - porting library • newgem myproject (or newgem . ) • rake manifest:refresh • rake install_gem

Deployment to RubyForge • create rubyforge account • create rubyforge project • rake deploy VERSION=X.Y.Z • website upload • gem/tar/zip upload

Native C extensions • C is faster than Ruby • External integration of existing C libraries

newgem - extconf generator • script/generate extconf • rake test • autotest

Demo • script/generate extconf stack • gem install ZenTest (includes autotest) • autotest

test/test_stack_extn.rb require "test/unit" $:.unshift File.dirname(__FILE__) + "/../ext/stack" require "stack.so" class TestStackExtn < Test::Unit::TestCase def test_init stack = Stack.new assert_equal([], stack.instance_variable_get("@arr")) end end

ext/stack/stack.c VALUE cStack; void Init_stack() { cStack = rb_define_class("Stack", rb_cObject); rb_define_method(cStack, "initialize", t_init, 0); }

ext/stack/stack.c cont... static VALUE t_init(VALUE self) { VALUE arr; arr = rb_ary_new(); rb_iv_set(self, "@arr", arr); return self; }

test/test_stack_extn.rb def test_push stack = Stack.new stack.push 3 stack.push 4 assert_equal([3,4], stack.instance_variable_get("@arr")) end

ext/stack/stack.c cont... static VALUE t_push(VALUE self, VALUE val) { VALUE arr; arr = rb_iv_get(self, "@arr"); rb_ary_push(arr, val); return arr; } VALUE cStack; void Init_stack() { cStack = rb_define_class("Stack", rb_cObject); rb_define_method(cStack, "initialize", t_init, 0); rb_define_method(cStack, "push", t_push, 1); }

Build and install • rake manifest:refresh • rake install_gem • “Building native extensions. This could take a while...”